Conventional valves for blocking and unblocking fluid flow include umbrella valves. A known umbrella valve assembly includes an umbrella valve positioned in a valve housing. The umbrella valve has a flexible umbrella. The umbrella is pushed away from a sealing surface (such as a valve seat) of the valve housing under a forward fluid flow allowing passage of the fluid around the umbrella. The umbrella is pushed against the sealing surface under a reverse fluid flow preventing passage of the fluid around the umbrella.
Still, scientists and engineers continue to seek improved umbrella valves and improved umbrella valve assemblies.